The U.S. Federal Communications Commission will aim to conduct auctions to sell spectrum now held by television stations to mobile broadband providers in mid-2015, the chairman of the agency said Friday.

It's important to release more spectrum for new, flexible uses, FCC Chairman Tom Wheeler wrote in a blog post. The FCC will balance demands for more commercial spectrum with the time the agency needs to run a successful auction, he said. The so-called incentive auction will involve a complicated process in which the FCC will auction off spectrum voluntarily turned over by TV stations in exchange for a cut of the winning bid.

"I have often defined the complexity of this multi-part simultaneous process as being like a Rubik's cube," Wheeler wrote. "As part of our auction system development, we will check and recheck the auction software and system components against the auction requirements, and under a variety of scenarios replicating real life conditions. Only when our software and systems are technically ready, user friendly, and thoroughly tested, will we start the auction."

Mobile carriers praised Wheeler's plan, which would auction spectrum in the 600 MHz band, one of the best bands of spectrum for providing mobile broadband service.

Wheeler "has laid out a thoughtful and deliberate approach designed to assure that the FCC conducts a successful auction," Sprint said in a statement. "The schedule acknowledges the complexity of choosing the best auction policies and procedures and the importance of taking the time necessary to develop an auction bidding system which will operate effectively."

The incentive auction will be a "complex task" for the FCC, Kathleen Ham, vice president of federal regulatory affairs for T-Mobile USA, said in a statement. "We are very supportive of getting it right and will work with the FCC to ensure the auction is a success, promoting competition, innovation and consumer benefit."

Grant Gross covers technology and telecom policy in the U.S. government for The IDG News Service. Follow Grant on Twitter at GrantGross. Grant's email address is grant_gross@idg.com.